Spinning liquor for artificial silks



Patented Dec. 21, 1937 PATENT OFFICE SPINNING LIQUOR FOR ARTIFICIALSILKS Samuro Yamamoto, Iriarai Machi, Ebara-gun,

Tokyo-fu, Japan, assignor to Shozaburo, Hashino, Iriarai Machi,Ebara-gun, Tokyo-fu, Japan No Drawing. Application May 4, 1932, SerialNo. 609,332. 'In Japan May 14, 1931 4 Claims.

This invention relates to the method of manufacturing artificial silk,which consists in pressing out fibroin solution for spinningintermingled with alkyl ester or alkyl salts, into salt solution oracidic solution from a nozzle. The object thereof is to regenerate silkyarn of excellent quality artificially by keeping the original solutionthick and viscous, that is, in good condition for spinning, withoutdestroying the fibroin substance excessively even after the lapse oftime.

The main object of my invention is to provide a method of manufacturingartificial silk of excellent quality, uniformity and durability.

In the art as heretofore practiced, silk fibre or fibroin is dissolvedin an alkaline solution containing a metal such as copper, nickel, etc.,and the solution is rendered more fluid by various means reducing itsviscosity in order to avoid the excessive decomposition of the fibroinwith the passing of time, which renders it impossible to spin it on anindustrially large scale as regenerated silk. Even if spun andcoagulated, it cannot be elongated finely during coagulation and theproduct has inferior quality with defects in tensile strength, deniersize and lustre. According to the present invention it is possible toregenerate silk yarn of superior quality on an industrially large scale,removing the above defects by intermingling methyl acetate, amylacetate, ethyl acetate and propyl acetate and other alkyl esters offormic acid, oxalic acid, citric acid, tartaric acid and acetic acid orthe chloride with the original solution for spinning which has silkfibre dissolved therein.

The following is an example of carrying out this invention intopractice:-

Add 01-10% of alkyl ester, as for example, methyl acetate, amyl acetate,ethyl acetate and propyl acetate, tothe known solvent for silk fibreprepared by dissolving copper hydroxide and nickel hydroxide in causticalkali solution with the addition of one or two of glycerin, glycol,sodium potassium tartr-ate and sugar and then proceed to dissolvefibroin in the solvent 'containing the alkyl ester thus prepared so asto form the desired solution which is of suitable 1. A spinning liquorfor artificial silk comprising a solution of fibroin in an alkalinesolution of a metallic compound of the class consisting of copper andnickel hydroxides with an alkyl ester of the class consisting of methylacetate, amyl acetate, ethyl acetate and propyl acetate and containingan added organic compound consisting of glycerine.

2. The method of preparing a spinning liquor for artificial silk, whichconsists in mixing an alkaline solution of a metallic compound of theclass consisting of copper and nickel hydroxides with an alkyl ester ofthe class consisting of methyl acetate, amyl acetate, ethyl acetate andpropyl acetate and dissolving fibroin in the resulting solution.

3. A spinning liquor for artificial silk comprising a solution offibroin in an alkaline Solution of a metallic compound of the classconsisting of copper and nickel hydroxides with an alkyl ester andglycol and tending to promote the viscosity of the solution. v

SAMURO YAMAMOTO.

